package com.twq.servlet;

import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;

//保存用户上一次访问的时间
public class CookieDemo01 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("UTF-8");
        resp.setCharacterEncoding("UTF-8");
        resp.setContentType("text/html;charset=utf-8");

        PrintWriter out = resp.getWriter();
//Cookie,服务器从客户端获取
        Cookie[] cookies = req.getCookies();//返回数组，说明Cookie可能存在多个
        //判断Cookie是否有值
        if(cookies!=null){
//            如果存在怎么办
            out.write("你上一次访问的时间是：");
            for (int i = 0; i <cookies.length ; i++) {
                Cookie cookie=cookies[i] ;
                //获取cookie的名字
                if (cookie.getName().equals("lastLoginTime")){
                    //获取cookie中的值

                    long lastLoginTime = Long.parseLong(cookie.getValue());

                    Date date = new Date(lastLoginTime);
                    out.write(date.toLocaleString());
                }
            }

        }else {
            out.write("这是你第一次访问本站");
        }
//        服务器响应一个Cookie

        Cookie cookie = new Cookie("lastLoginTime", System.currentTimeMillis()+"");

       //cookie有效期为一天
       cookie.setMaxAge(24*60*60);
        resp.addCookie(cookie);
    }
}
